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Herbicide Resistance

Key points in this POSTnote include:

• Agricultural crop yields are reduced when unwanted plants (weeds) compete with crops. Synthetic herbicides are widely used to control weeds.
• A wide variety of weeds have shown resistance to a range of herbicides, which reduces chemical control options.
• The EU regulates the use of herbicides. Changes to the regulations in 2009 have reduced control options further.
• More diverse management strategies that include non-chemical methods, such as spring cropping, may help conserve the effectiveness of herbicides and contribute to reducing resistant weed numbers.